Washington Park Arboretum received this clone from USDA Plant Introduction Station in Glenn Dale, Maryland as PI 256000. -- Information from Randall C. Hitchin, Living Collections Manager, University of Washington Botanic Gardens, January 2006.USDA Plant Introduction Station received scions from Hillier and Sons, Winchester, England in March 1959 -- USDA Plant Inventory Volume 167.
Possibly Decaisne's Pyrus bollwilleriana, first described by Lindley in 1437. Decaisne (1858, translated from French by M. Westwood in 1996) wrote 'The pear of Pollwiller is a remarkable example of the persistence of the characters of a hybrid tree, propagated for three centuries by grafting, and which contradicts everything said on the subject of the disappearance and the degeneration of our ancient varieties of fruit trees.' In 1860 Decaisne collected 450 fruits, found only 13 well formed seeds - seedlings varied from pear-like to sorbus-like.
Decaisne quoted from Chabraeus, 1666: 'This is the most rare and beautiful genus of pear, up to the present, and we have never seen it except in Pollvillam in Alsatia and the garden of the Prince Montbelgardi. Possibly the genus is the alpine Sorbus?'
Decaisne quoted from J. Bauhin, 1619: 'The pollwiller pear is considered the rarest and most beautiful genus of pear by the noble Barons of Pollwiller; they call it Rotbirle.'